GB2026575A

GB2026575A - Tunnelling machines

Info

Publication number: GB2026575A
Application number: GB7922517A
Authority: GB
Original assignee: BADE AND THEELEN GmbH
Current assignee: BADE AND THEELEN GmbH
Priority date: 1978-07-01
Filing date: 1979-06-28
Publication date: 1980-02-06
Also published as: JPS641639B2; DE2829053A1; DE2829053C3; DE2829053B2; GB2026575B; JPS557394A

Abstract

A shield for machine tunnelling is disclosed with a working face supported by compressed air or liquid, in the case of which behind a cutting wheel (42), working over the complete cross-section, at least one pressure-tight bulkhead (1') is placed and there is a system for keeping the supporting fluid under pressure and undertaking transport of material cut from the working face. The cutting wheel (42) and its driving shaft or the gearing housing (47) is guided in a bearing system, which is supported in the bulkhead (1') so as to be able to be moved radially. The shaft or the gearing housing (47) is guided in the bearing system so as to be able to be moved in the length-direction and the bearing system has spherical support faces for a limited change in slope motion and, at the same time, the necessary sealing effect between the front working space (44) and the space inside the tunnel is produced, though the cutting wheel (42) being placed in the tunnelling or working space in front of the bulkhead (1') and its driving unit is placed behind the bulkhead (1'). <IMAGE>

Description

SPECIFICATION A bearing for the cutting wheel of a shield for tunneling with the working face supported by compressed air or liquid The invention relates to a shield for machine tunneling with working face supported by compressed air or liquid, in the case of which behind the cutting wheel, working over the complete cross-section, at least one pressure-tight separating wall is placed and there is a system for keeping the supporting fluid under pressure and undertaking transport of material cut from the working face.

Shield tunneling machines with a system for supporting the working face have been put forward in a great number of different forms and frequently the complete tunnel is completely full of compressed air, more specially when driving tunnels below the ground water level. Because in such a case great quantities of air are forced out through the working face, the price of tunneling is naturally increased.

Furthermore on using compressed air in the tunnel, there is in all cases a shortcoming because the conditions are unhealthy for the workers. Forovercom- ing these shortcomings, water-tight shields have been designed, in which only the space in front of the front bulkhead is under the necessary air or liquid pressure so that there is the good effect that behind the front bulkhead in the tunnel space work is able to be undertaken under atmospheric pressure, and conditions are not made unhealthy by the compressed air, this being equally true if the support for the working face in front of the bulkhead is effected by compressed air or if it is effected by liquid.

In one old form of such a water-tight shield (see the German Auslegeschrift specification 2,227,083) the shaft of the cutting wheel is supported horizontally in a bearing system, which, however, does not let the cutting wheel be changed in slope or moved radially or in the direction of its length, so that guiding and positioning of the water-tight shield becomes very hard, more specially when turning corners. In changing the position or direction of the shield with normal gear, there is a great loss in time, this naturally making for a higher price of the tunneling operation.Furthermore with the old bearing design, it is not readily possible to make certain of a seal between the front working space in front of the bulkhead, which is under compression, and the tunnel space coming behind the bulkhead, which is at the pressure of the atmosphere, and at the same time to make certain of taking up the high reaction forces produced on working with a cutting wheel.

One purpose of the present invention is that of designing a shield, in the case of which the cutting wheel is on the one hand completely and usefully sealed, while on the other hand may be moved in all necessary directions for making it more readily possible for the shield to be positioned and changed in direction.

In the invention the cutting wheel and its driving shaft or the gearing housing is guided in a bearing system, which is supported in the bulkhead so as to be able to be moved radially, the shaft or the gearing housing is guided in the bearing system so as to be able to be moved in length-direction and the bearing system has spherical support faces for a limited change in slope motion and, at the same time, the necessary sealing effect between the front working space and the space inside the tunnel is produced, though the cutting wheel is placed in the tunneling or working space in front of the bulkhead and its driving unit is placed behind the bulkhead.

In one form of the invention the gearing housing of the driving shaft are guided in a bearing system which is supported in a bulkhead by way of a sealing and plain bearing ring so asto make radial motion possible, and a bearing ring is used for guiding the gearing housing so as to make a change in position in the length-direction possible, the bearing ring has, on its inner face, plain bearing faces with seals and on the outside has generally spherical support faces with seals, and between the support faces a connection ring is placed, whose cutouts let radial motion of the bearing system bodily take place in relation to the bulkhead.

In the case of one form of the invention of good effect, the seals in front of the bulkhead and in the tunnel space behind the bulkhead are able to be exchanged against new seals seperately, so that at the positions in question at least one seal still gives the necessary sealing effect. Furthermore, in the invention the guide rails supporting the gearing housing are designed so as to be able to be exchanged for new ones in such a way that a radial change in position of the gearing housing is made possible in every direction.

One useful effect of the invention is that while still make use of the good effect of an atmospheric air pressure in the inner space of the shield, that is to say behind the bulkhead, the shield may be very much more readily changed in position and in direction, because the bearing system, guiding the gearing housing and the driving shaft, makes possible motion in three directions, that is to say a radial motion, a change in position in the length-direction and, lastly, a change in slope. Furthermore, at the same time, there is the desired sealing effect, which does not come to an end even if parts of the seal have to be exchanged against new ones.

In the accompanying drawings one working example of the invention is to be seen.

Figure.1 is a diagrammatic view and an upright section of the front part of a shield for machine tunneling with a liquid-supported working face.

Figure 2 is a view, on a greater scale, of the middle part of Figure 1 with the cutting wheel having its bearing system and gearing.

Figure 3 is a section of the complete bearing system for the gearing housing and the driving shaft.

Figure 4 is a front view of the bearing system, marked by arrow 99 in Figure 3, with a view of the parts making possible a radial change in position of the bearing system.

In the view of Figure 1 the shield casing is numbered 40, the front shield edge of the shield casing is numbered 41 and the cutting wheel is numbered 42.

The bulkhead is numbered 43, the bulkhead being used for sealing off the inside of the shield from the part44 in which there is a pressure greater than atmospheric pressure. The pressure cylinders are numbered 45 and are used for moving the shield in relation to the tunnel lining 46. The cutting wheel 42 is fixed to a driving shaft 50 and its bearing is so designed that the cutting wheel is able to be changed in position in the length-direction and to be changed in slope. Furthermore the placing of the bearing on the gearing housing 47 makes possible a radial motion of the gearing housing. The part behind the bulkhead is numbered 48 and here there is atmospheric pressure in order to make for healthier conditions within the tunnel driving shield and the tunnel itself and for stopping any compressed air disease.

In Figure 2 in the middle part of the cutting wheel 42 with the bearing 2 of the invention is to be seen.

The bearing 2 is supported on the bulkhead 1'.

Behind the bearing system there is the gearing 61, which is generally of old design and, for this reason, is not in need of any detailed account.

In Figure 3 details of the bearing system are to be seen, which lets a change in position in the lengthdirection and a change in slope of the cutting wheel 42 take place. Furthermore it makes possible a radial motion while sealing is made certain of at the same time. The gearing housing 47 is, in this bearing system, supported so as to be able to be changed in position in the length-direction. Between the gearing housing 47 and the bearing system there are seals 18 and 20'. The bearing is supported on the bulkhead 1' by way of its sealing and support faces 1. As will be seen from Figure 3 in this respect, this way of supporting the housing 3 lets a radial motion take place.

The support with respect to the gearing housing 47 is by way of a bearing ring 2, which at the front and behind it has cutouts or hollows for the seals, noted earlier, 18 and 20'. In these hollows there are stuffing boxes 5, able to undergo adjustment by way of adjustment screws 23. In the middle part of the bearing ring 2, able to be moved in the length-direction, there is a hollow 33 making possible change in position radially. The sealing of the housing 3 with respect to the sealing and support faces is undertaken by the seals 19 and 20 which are able to undergo adjustment like stuffing boxes. These seals 19 and 20 are positioned by stuffing boxes 6, which may undergo adjustment by fixing parts 26 to 28. In addition to the seals noted so far, there are furthermore static seals 22 in the plain bearing face 32.There is a fixing screw 29 with seals 21 for keeping in position the connection ring 4, which because of its design at the inner support face makes possible a change in slope. Furthermore, for positioning the plain bearing face 32 a keeper ring 7 is present, which is placed resting on the inner side against static seals 7'. This keeper ring 7 is positioned by adjustment screws 24 with a washer 15. A lubrication nipple for greasing is present at 17.

In Figure 4 looking in the direction of the arrow 99 of Figure 3, it is possible to see the general placing of the bearing system in the bulkhead from the front.

There are guide rails 60, which because of changes in thickness made as desired may be used for posi tioning the bearing system in relation to the axes of the shield, that is to say to make possible a radial change in position and for small adjustments in position after the main adjustment has taken place.

Claims

1. A shield for machine tunneling with the working face supported by compressed air or liquid, in the case of which behind the cutting wheel, working over the complete cross-section, at least one pressure-tight bulkhead is placed and there is a system for keeping the supporting fluid under pressure and undertaking transport of material cut from the working face, characterised in that the cutting wheel is guided in a bearing system, which is so movingly supported in a bulkhead and itself is so designed that the cutting wheel is guided to make possible, in front of the bulkhead, changes in position radially and in the length-direction and, at the same time, changes in slope in all directions and in that the bearing system has parts which, even with such changes in position and direction being possible, makes possible at any time a complete sealing effect between the front pressure space and the inside of the tunnel behind the shield.

2. A shield as claimed in claim 1, characterised in that the bearing system is guided by way of the two outer housing valves in the bulkhead at the plain bearing face for radial motion, in that the bearing ring has spherical support faces, by which it is placed so as to be able to be changed in slope in the outer housing and in that the bearing ring is formed on the inner side for letting the cutting wheeel be changed in position in the length-direction and in that the housing halves are joined by way of the connection ring to take the form of a common bearing housing.

3. A shield as claimed in claims 1 and 2, characterised in that all necessary seals are present twice over, that is to say, in the one case, in front of the bulkhead in the pressure space and, in the other case, one is behind the bulkhead in the tunnel space.

4. A shield as claimed in any one of claims 1 to 3, characterised in that the seals may undergo adjustment and may be exchanged against new seals in such way that, on exchanging one seal for a new one, one group of seals before or to the back of the bulkhead keeps its full sealing effect.

5. A shield as claimed in any one of claims 1 to 4, characterised in that the bearing housing with its support plates is supported by way of guide rails in the bulkhead in such a way that on exchanging the guide rails other guide rails it is possibleforthe bearing housing to be changed in position radially in any desired direction.

6. A shield as claimed in any one of claims 1 to 5, substantially as described above, with reference to and as illustrated in the accompanying drawings.